Hello there,
I am Mailchimp expert with 4 years of working experience. I have worked on lots of Mailchimp project.
I have used both ESP's free account.
It depened's on your requirements, which one is best for you.
Please and these questions over chat
- How did you collect your emails?
-Are they subscribed?
-How many emails you wanna send everyday?
Let's discuss over chat. Waiting for your response.
Kind regards,
Abul Kalam